Feeding mechanism for extrusion machines



Jan. 29, 1935. J. w. HOFFECKER FEEDING MECHANISM FOR EXTRUSION MACHINES Filed April 5, 1935 5 Sheets-Sheet l Jiuz h/Zifojfzckez Jan. 29, 1935. J. w. HOFFECKER 1,939,616

' FEEDING MECHANISM FOR EXTRUSION MACHINES FiledAprilfi, 1933 3 Sheets-Sheet 2 Clfe Jan. 29, 1935. J. w. HOFFECKER FEEDING MECHANISM FOR EXTRUSION MACHINES Filed April 5, 1953 3 Sheets-Sheet 3 Patented Jan. 29, 1935 UNITED STATES- FEEDING ,MEGHANISM VFOREXTRUQSION MACHINES John W. Hofl 'ecker, Wilmington, DeL, assignor, by mesne assignments, to Bond Manufacturing Corporation, Inc., Wilmington, Del., a corporation of Delaware Application April 5, 1933, Serial No. 664,611

3 Claims.

This invention relates to improvements in feeding mechanism and particularly to mechanism for feeding granular materials, such as comminuted cork. g

The primary object is to provide a feeding mechanism of exceedingly simple and comparatively inexpensive design, but one which possesses a high degree of efiiciency.

Another object is the provision of a feeding mechanism that can, readily be adjusted to vary and regulate the quantity of material fed thereby. A still further object is the provision of a feed mechanism, especially adapted for feeding comminuted cork to a plurality of molds, wherein the quantity of cork delivered to any one or more molds may be varied independently of the quanty fed to other molds.

Another object is to provide a feed mechanism which will not unduly agitate the cork, or to such an extent as to be detrimental to the binder. With these and other objects in View, the invention consists in certain details of construction and combinations and arrangements of parts, all as will hereinafter be more fully described and the novel features thereof particularly pointed out in the appended claims.

In the accompanying drawings,

Figure 1 is a top plan view, partly broken away, of a cork molding machine with the present invention applied thereto;

Fig. 2 is an end view, partly broken away and partly in section;

Fig. 3 is a sectional view taken transversely of the feeding mechanism;

Fig. 4 is a'sectional view on the line 4-4 of Fig. 3; and

Fig. 5 is a detail perspective view on the reciprocatory frame carrying the mold plungers.

While the present feeding mechanism is susce'ptible of use in various types of apparatus, it is especially adapted for use in a cork molding machine of the type disclosed in Patent No. 1,453,617, dated May 1, 1923, and reference is made to that patent for a detailed description of the machine proper shown in the present instance. Suffice it to say, the machine illustrated herein is designed to have a large output through duplication of treating chambers or molds and is adopted for illustrative purposes inasmuch as it represents a commercial development now in use. In this machine there is provided a hopper for reception of the comminuted cork which has previously been impregnated with a binding material, and the cork is fed by one or more of the present mechanisms to a multiplicity of molds each ofwhich may be a duplicate of the other.

Except for the reference to general characteristics of the machine, therefore, the description of one feeding mechanism and one moldwill be sufiicient. As disclosed in the patent before men'- tioned, the present apparatus comprises a substantial base or main frame 10 on which there is superposed a hopper 11, the hopper preferably being divided into sections. Each section of the hopper is adapted to supply cork to two series of molds arranged opposite each other. For this purpose, the hopper is formed with intermediate downwardly diverging walls 12, thereby forming throats through which the feeding mechanism to be later described feeds the cork intohopper bottoms 13. The hopper bottoms 13 are preferably in the form of long castings through which a series of tube or chamber openings are formed to intersect thechannel formed in said bottom and each opening is adapted for the reception of, or to form a part of a treating tube or molding chamber 14, through which the cork is extruded.

The feeding mechanism embodies means for delivering cork from the bottom 13 into each of the tubes 14, these feeding means preferably taking the form of a plunger 15 and all of the plungers are adjustably connected at their inner ends with a reciprocatory frame 16. The frame 16 which is of necessity of a heavy and exceedingly rigid construction, is preferably formed with cross heads 17. adapted to slide in rigid guide-Ways 18 at each extremity of the mam-means is reciprocated so as to impart a longitudinal movement to the plungers, by means of eccentrics 19 mounted on a shaft-20 journaled in suitable bearings in the main frame. Said eccentrics in turn workin slidingblocks 21 confined between ways formed by depending extensions 22 of the frame 16. R0- tary motion is imparted to shaft 20 through the medium of gearing indicated at 23, 23a, 23b, from a drive shaft 24 to which a motor or prime mover may be connected in any suitable way. The series of tubes or mold chambers are provided with means as indicated diagrammatically at 25, 25a, whereby, their temperature conditions may be accurately regulated in transverse zones. That portion of each tube projecting into the cavity in the casting has its upper portion cut away as at 14a in order to permit entry of cork into the tube. This cut away end portion of the tube is usually termed the throat of the tube.

Journaled in the end walls of the casting 13 is a shaft 26 carrying a cylinder 27 on whose periphery is formed a plurality of longitudinally extending grooves or pockets 28. Cylinder 2'7 closes the throat of hopper 10, but by reason of the cork in the hopper having access to grooves or pockets 28, a substantially constant volume of cork will be removed from the hopper and delivered in the cavity of casting 13 by each groove upon rotation of the cylinder. Grooves 28 extend the full length of the cylinder and to evenly distribute the cork from the grooves among the.

several extrusion tubes, partitions 29 are provided in the casting 13 betwee-neach two-juxtaposed tubes, each partition preferably being tapered upwardly to prevent particles of cork lodging thereon. The cylinder 27 is rotated intermittently to advance any desired numberof grooves at each movement, the number of grooves advanced determining the volume of each increment of cork delivered to the individual tubes, and each increment of cork so deposited in the respectivetubes .is forced into the tubes by the plungers 15, while the cylinder is stationary and before the next increment is delivered to the tubes.

ihe intermittent rotary motion of cylinder 2'? must be timed with respect to the reciprocation of crosshead 16 and plungers 15, so that the cylinder will be stationary when the plungers are advanced and will be rotated to deliver cork to the tubes as the plungers are retracted.- The preferred arrangement for coordinating the movements of these elements comprises extensions 30 projecting forwardly from cross head 17 and pawls 31 vertically movable in said extensions. Each pawl has a threaded stem 32 extending through a depending guide bracket 33 mounted on extension 30 and springs 34tnterposed between the pawls and the lower ends of said brackets yieldingly urge the pawls into engagement with ratchets 35 on the ends of shaft 26 which protrude through the end walls of the casting 13. The upward movement of pawls 31- when' moved forwardly and out of contact with ratchets 35, is limited by nuts 36 on the threaded pawl stems engaging the under faces of the lower ends of brackets 33. By adjusting the nuts on said pawl stems, the movement allowed the pawls may be varied. In the machine illustrated, the throw imparted to the cross head and the movement allowed the pawls issuch that the feed cylinder is adapted to be rotated three teeth on the ratchets, or, three grooves on its periphery, the number of grooves on the cylinder corresponding to the number of teeth on the ratchet.

As will be understood, each increment of cork deposited in the cavity between any two partitions 29 during any one movement of cylinder 27 is forced into the tube communicating with that cavity before the next movement of the cylinder to deliver the next or succeeding increment of cork.

With the present construction, it will be seen that there is very little agitation of the cork in the hopper by the feed cylinder. This is quite advantageous as compared with, the results obtained when the plungers areutilized for feeding the cork out of the hopper because this latter arrangement causes such agitation of the cork as to be detrimental to the binder. Also, it will be appreciated that by blocking out, so to speak, portions or one or more grooves or pockets in the feed cylinder, the quantity of cork fed to any one or more molds may be varied at will. It will also be, appreciated that the cross sectional shape of the molds may be varied to produce different shapes, i. e., instead of cylindrical molds, strips can be formedby' utilizing molds of rectangular cross section.

What I claim is:

1. In a feed machanism, the combination of a hopper for the material to be fed, a series of pockets journaled for movement through the lower portion of said hopper, a reciprocatory plunger carriage, a plunge-r carried by said carriage and a reciprocatory'member movable in unison with said plunger for imparting a rotary motion to said pockets, the extent of movement imparted to the pockets being variable independently of the extent of movement of said carriage.

2. In a feed mechanism, the combination of a hopper for the material to be fed, a seriesof pockets journ'aled for movement through the lower 'portion of thehopper from a point within to a point without said hopper, a ratchet associated with said pockets, a reciprocatory pawl movable into and out of engagement with said ratchet for rotating said pockets, and means for adjusting said pawl relatively to'said ratchet for varying the number of pockets moved from within to a point without the hopper by engagement of the pawl with said ratchet.

3.'In a feed mechanism, the combination of a hopper for the material to be fed, a series of pockets journaled for movement through the lower portion of the hopper from a point within to a point without said hopper,.a ratchet associated with said pockets, a reciprocatory pawl yieldingly urged toward said ratchet, means for reciprocating said pawl to revolve said pockets, and means" for varying the normal distance between said pawl and ratchet radially of the ratchet to vary the number of pockets moved from within to a point without the hopper each time the pawl actuates said ratchet and pockets.

JOHN W. HOFFECKER. 

